feat(opencode-go): add muse-spark-1.3-contributor and fix parallel tool calls on Responses paths (#3819)

- Add muse-spark-1.3-contributor as responses-only model on OpenCode Go with dedicated executor
- Key Responses→chat streaming tool calls by item_id to prevent parallel tool calls merging into index 0
- Standardize tool coercions and call_id clamping in Responses API translation

open-sse/config/providerModels.js

@@ -50,7 +50,7 @@ export function findModelName(aliasOrId, modelId) {
 }
 
 export function getModelTargetFormat(aliasOrId, modelId) {
-  if ((!aliasOrId || aliasOrId === "oc" || aliasOrId === "opencode") && isMuseSparkModel(modelId)) {
+  if ((!aliasOrId || aliasOrId === "oc" || aliasOrId === "opencode" || aliasOrId === "ocg" || aliasOrId === "opencode-go") && isMuseSparkModel(modelId)) {
     return FORMATS.OPENAI_RESPONSES;
   }
   const models = PROVIDER_MODELS[aliasOrId];